Start center crashes MuseScore if there is no Internet connection

• Nov 26, 2018 - 04:09
Reported version
P1 - High
S1 - Blocker

Internet connection in Musescore 3 is blocked by a filter on my computer. If the Start Center opens up, which it won't if the Internet connection doesn't occur, then it crashes the program.
So far, what I've found, is that if the Start Center opens, but can't connect to the Internet, it crashes. If Internet connection doesn't happen, then the Start Center doesn't open up at all.
This may just be caused by the filter's delay in stopping connection that causes the Start Center to open, then crash. If so, then the Start center not opening could be intentional and this is just a rare flaw in the code.
However, an offline start center could be useful, if not just for this problem.


Workaround No Yes

Workaround: Use the -w option
Actually that workaround is the fix for the request to have an offline start center (it is a workaround for the crash though

Doesn't crash for me, Windows 10 Enterprise, LAN cable disconnected and switched to "Flight Mode" (disable WiFi etc.) to make sure there's no internet access.

I could reproduce occasionally on Windows. It could crash 5-10 seconds after closing Start Center. I believe it relates to signals/slots processing

I've also experienced something similar with Musescore 2.3.2. I worked on a score on my home computer and saved it to my OneDrive directory. Then I worked on it on a different machine and saved it, so the original OneDrive file was rewritten. At home I opened Musescore - it started but was unresponsive. The reason was the score file had been marked as changed but probably due to my faulty wifi at that time OneDrive somehow couldn't downloaded it. I saw a bottom-rigtht corner notification about downloading (progress 0%) and I think musescore start center couldn't get the score preview so it was unresponsive. I didn't have the patience then so I killed the process.

Later I've come up with this: it may or may not be related to what you've reported so far. Although I haven't managed to crash the application, I did manage a good reproducible 1-2 minute freeze which is maybe not desirable anyway.

Steps for both 2.3.2 and
(version OS: Windows 10 (10.0), Arch.: x86_64, MuseScore version (64-bit):, revision: f2e1c8d )

you need to have a OneDrive account and NetBalancer installed on your system (download it from, 15-day free trial)

  1. open/create any musescore file and save it to your OneDrive folder
  2. close musescore
  3. open windows explorer, go to the OneDrive folder, right click on the file from step 1 and click "Free up space"
  4. open netbalancer, go to Edit->Settings, in "Limit all system traffic" section set both download and upload values to 0.1 and click on their checkboxes, press Apply
  5. open musescore, if it's not already unresponsive, open File->Start Center
  6. a bottom-right OneDrive notification about downloading the file should appear, click "Cancel download" and then again "Cancel download"

... it takes over 1 minute for Musescore to get over that

Priority P0 - Critical P1 - High
Regression Yes No

Rare case which we should address asap after release. Not a regression, it happened in all versions.